@inproceedings{paper,
          eprintid = {20406},
             month = {June},
      official_url = {http://www.thinkmind.org/index.php?view=article&articleid=icwmc_2011_2_40_20146},
            author = {K. C. H. {Blom} and M. D. {van de Burgwal} and K. C. {Rovers} and A. B. J. {Kokkeler} and G. J. M. {Smit}},
         num_pages = {6},
          keywords = {Blind beamforming, CMA, Hierarchical arrays},
        pres_types = {Talk},
       ispublished = {Published},
         publisher = {Xpert Publishing Services},
           isbn_13 = {978-1-61208-140-3},
      howpublished = {http://eprints.eemcs.utwente.nl/20406/},
          location = {Luxembourg},
       event_dates = {19-24 Jun 2011},
        event_type = {Conference},
   research_groups = {EWI-CAES: Computer Architecture for Embedded Systems},
         booktitle = {Seventh International Conference on Wireless and Mobile Communications,  ICWMC 2011, Luxembourg},
          refereed = {Yes},
  research_programs = {CTIT-WiSe: Wireless and Sensor Systems},
  research_projects = {SeaSTAR: Underwater Monitoring Platforms, Beamforce: CMOS Beamforming Techniques},
             title = {Angular CMA: A modified Constant Modulus Algorithm providing steering angle updates},
          abstract = {Conventional blind beamforming algorithms have no direct notion of the physical Direction of Arrival angle of an impinging signal. These blind adaptive algorithms operate by adjusting the complex steering vector in the case of changing signal conditions and directions. This paper presents Angular CMA, a blind beamforming method that calculates steering angle updates (instead of weight vector updates) to keep track of the desired signal. Angular CMA and its respective steering angle updates are particularly useful in the context of mixed-signal hierarchical arrays as means to find and distribute steering parameters. Simulations of Angular CMA show promising convergence behaviour, while having a lower complexity than alternative methods (e.g., MUSIC).},
     international = {Yes},
             pages = {42--47},
              year = {2011}
}

@mastersthesis{thesis,
          eprintid = {18532},
      howpublished = {http://eprints.eemcs.utwente.nl/18532/},
             month = {December},
            author = {K. C. H. {Blom}},
         num_pages = {77},
       supervisors = {G. J. M. {Smit} and A. B. J. {Kokkeler} and M. D. {van de Burgwal} and K. C. {Rovers}},
          keywords = {Adaptive beamforming, DVB-S},
   research_groups = {EWI-CAES: Computer Architecture for Embedded Systems},
  research_programs = {CTIT-WiSe: Wireless and Sensor Systems},
            school = {Univ. of Twente},
  research_projects = {Beamforce: CMOS Beamforming Techniques, NEST: Netherlands Streaming Reconfigurable digital antenna processor},
          abstract = {Phased array antennas are made up of multiple smaller antenna elements. Constructive interference of received waveforms results in directivity of a phased array antenna. The creation of angular regions with high sensitivity to receive signals from a desired direction is called beamforming. Mobile reception of Digital Video Broadcasting Satellite (DVB-S) signals is an interesting application of beamforming. A phased array antenna mounted on top of a vehicle should be able to electronically track the desired satellite signal during dynamic behaviour of the vehicle. This thesis discusses techniques to accomplish that goal.
The proposed system consists of a beamformer, an adaptive steerer and parts of the original DVB-S receiver. The proposed system uses phase shift based beamforming. A steering vector contains the required phase compensations to control the directivity of the phased array. The steering vector weights have to dynamically adapt to changing signal conditions. The latter is done by the adaptive steerer.
DVB-S signals contain no reference signal that can be used for steering. Therefore, the adaptive steerer uses structural properties of the signal to perform steering. Such an adaptive steerer belongs to the class of blind beamforming algorithms. The structural property of interest for a DVB-S signal is its Quadrature Phase-Shift Keying (QPSK) channel modulation. Movement of the phased array affects the beamformer output. If the phase reference of the array is centered then translational movement of the array leads to rotation of the QPSK constellation. Rotational movement of the array leads to the an orthogonal effect, a modulus decrease of the QPSK symbols. Two blind beamforming algorithms are discussed to adjust the steering vector weights based on these orthogonal effects: the Constant Modulus Algorithm (CMA) algorithm and the extended CMA algorithm. Both algorithms define a cost function that is minimized using a gradient descent.
For simulation of the proposed system vehicle dynamics are modelled to generate antenna data that contains the effects of rotational and translational movement of a vehicle. Execution of the extended CMA algorithm for this antenna data has shown the algorithm can track the desired DVB-S signal during the vehicle dynamics.
A short complexity analysis of extended CMA is performed to facilitate a later hardware implementation of the algorithm. Timing requirements are derived and it is shown that the computational complexity of extended CMA grows linear with the number of simultaneously tracked sources and the number of antenna elements.},
             title = {DVB-S signal tracking techniques for mobile phased arrays.},
       institution = {Univ. of Twente},
              year = {2009}
}

@misc{nvidia,
			title = {Nvidia CUDA Compute Unified Device Architecture programming guide v1.0},
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			author = {Nvidia},
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